How many moles of calcium are in a 351 kg sample? use "e" for "*10" and use significant figures?

In order to know the number of moles from the given mass, the conversion factor to be used is the average atomic mass of Calcium which is equal to 40.08 g/mol. But first, let's convert mass from grams to kilograms knowing that there are 1,000 g in every 1 kg.

Mass = 351 kg * 1,000g/1 kg = 351,000 grams

Number of moles = 351,000 g * 1 mol/40.08 g = 8,757.5 moles Calcium